1. Technical Field
Exemplary embodiments of the present disclosure relate to lateral double diffused MOS (LDMOS) transistors.
2. Related Art
Integrated circuits having functions of both a controller and a driver may be employed in smart power devices. Output circuits of the smart power devices may include lateral double diffused MOS (LDMOS) transistors operating at high voltages. Thus, breakdown voltages of the LDMOS transistors, for example, a drain junction breakdown voltage and a gate dielectric breakdown voltage are important factors that may directly influence the stable operation of the LDMOS transistors. In addition, on-resistance (Ron) of the LDMOS transistors is also an important factor that may influence electrical characteristics of the LDMOS transistors. To reduce the on-resistance of the LDMOS transistors, a doping concentration of drift regions between drain regions and channel regions should be increased. However, in the event that the doping concentration of the drift regions increases, the drain junction breakdown voltage may be reduced. That is, in the LDMOS transistors, the on-resistance and the drain junction breakdown voltage may have a trade-off relationship.